1. Field of the Invention
The present invention relates to an optical switch, and in particular to an optical switch that uses a deflection of light by a movable mirror array.
2. Description of the Related Art
A structure in which light from an optical fiber array for input is switched to an optical fiber array for output is hitherto known. For example, in a structure disclosed in Japanese Patent Application Laid-open Publication No. 2001-174724, first of all, light that is emitted from the optical fiber array for input passes through a lens array for input. Light passed through the lens array is reflected at a first MEMS (micro electro mechanical system) mirror array and a second MEMS mirror array. The reflected light passes through a lens array for output and is incident on the optical fiber array for output. Here, an angle of inclination of each mirror in the first MEMS mirror array and the second MEMS mirror array is controlled by an electric signal. Accordingly, light from the optical fiber array for input is deflected according to the angle of inclination of each mirror by the electric signal. The deflected light is output to a desired port for output (optical fiber for output).
In the structure mentioned above, when a supply of voltage to the MEMS mirror array is stopped, a control of the angle of inclination of the mirror by the electric control signal stops functioning. Due to this, it is not certain as to which output port the reflected light is to be output to. Therefore, light from the optical fiber for input is output to an output port (optical fiber for output) to which the light is not intended to be output. As a result, there is a possibility of inducing a malfunctioning of an optical switch, and consequently an optical communication system in which this optical switch is used.